• 한국건설순환자원학회논문집
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• 제7권4호
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• pp.323-332
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• 2019

건설 방수재로 사용되는 고무아스팔트 씰재에 대한 한국 및 중국의 공동 품질관리 규정 제정을 위해 양국의 재료 및 품질기준 현황을 조사하고, 향후 방향을 제시한 연구다. 고무아스팔트 씰재에 대한 한중 무역교류가 추진되고 있 있으나, 국가 간에 제시된 품질기준이 달라 제품에 대한 품질 검증의 어려움이 있고, 이를 해소하기 위해 양국의 현황을 파악하여 공동 품질관리 규정 제정의 필요성을 제시하였다 .한국과 중국의 고무아스팔트 씰재에 대한 구성 재료 비교, 품질관리 기준(성능평가 항목)의 비교 결과, 구성 재료에 있어서 방수 성능을 발현하는 주성분 원료인 "아스팔트와 고무"의 사용 비율에 차이가 있고, 부원료(충전제, 증점제, 접착제 등)의 사용 소재 종류도 다르게 나타났으며, 성능평가 항목에 있어서도 양국의 요구 성능 항목이 크게 다르다는 것을 파악되었다. 이러한 문제을 해소하기 위하여 일반적으로 ISO(국제표준기구 : International Organization for Standardization)에서 제시한 표준 기준을 활용하는 등의 대안이 있으나 고무 아스팔트 씰재에 대한 방수재 ISO 표준은 전무하며, 한중간 무역 교류를 위하여 ISO 규격을 제정하기에는 소모되는 시간이나 비용에 따른 경제적 여건이 불합리한 상황이다. 이에 본 연구에서는 한중 양국 간에 공동으로 적용할 수 있는 품질규격을 제정하여 상호 무역 교류 시 이를 적용함으로써 제품에 대한 물성파악이 용이한 국제공동규격 제정을 위한 성능평가 요소로써 주요 성능 항목으로 "화학저항성능, 투수저항성능, 온도안정성능, 습윤면 부착성능"을, 부가 성능 항목으로 "균열 거동 대응성능", "점도", "고형분" 등 7가지 항목을 제시하였다.

• International Journal of Concrete Structures and Materials
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• 제5권1호
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• pp.57-64
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• 2011

An extensive database has been constructed of reinforced concrete (RC) beam-column connection tests subjected to cyclic lateral loading. All cases within the database experienced joint shear failure, either in conjunction with or without yielding of longitudinal beam reinforcement. Using the experimental database, envelope curves of joint shear stress vs. joint shear strain behavior have been created by connecting key points such as cracking, yielding, and peak loading. Various prediction approaches for RC joint shear behavior are discussed using the constructed experimental database. RC joint shear strength and deformation models are first presented using the database in conjunction with a Bayesian parameter estimation method, and then a complete model applicable to the full range of RC joint shear behavior is suggested. An RC joint shear prediction model following a U.S. standard is next summarized and evaluated. Finally, a particular joint shear prediction model using basic joint shear resistance mechanisms is described and for the first time critically assessed.

• 한국인쇄학회지
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• 제18권2호
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• pp.55-68
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• 2000

Joint photographic experts group (JPEG) is a standard still-image compression technique, established by the international organization for standardization (ISO) and international telecommunication standardization sector (ITUT). The standard is intended to be utilized in the various kinds of color still imaging systems as a standard color image coding format. Because JPEG is a lossy compression, the decompressed image pixel values are not the same as the value before compression. Various distortions of JPEG compression and JPEG recompression has been reported in various papers. The Image compressed by JPEG is often recompressed by same type compression method in JPEG. In general, JPEG is a lossy compression and the quality of compressed image is predicted that is varied in according to recompression Q-factor. In this paper, four difference color samples(photo image, gradient image, gradient image, vector drawing image, text image) were compressed in according to various Q-factor, and then the compressed images were recompressed according to various Q-factor once again. As the result, this paper evaluate the variation of image quality and file size in JPEG recompression and recommed the optimum recompression factor.

• 전자통신동향분석
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• 제38권2호
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• pp.66-74
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• 2023

Holography is the most promising 3D imaging technology to faithfully record and reproduce light information. In addition, it is widely explored in metrology for applications such as microscopy and tomography because it can accurately measure 3D shapes. However, the data size of a digital hologram is very large, and the data characteristics are notably different from those of conventional 2D images. The Joint Photographic Experts Group (JPEG) is a group of experts from the International Organization for Standardization/International Electrotechnical Commission. This group develops and maintains standards for still image compression. In 2014, the JPEG released a new standard for 3D image compression called JPEG Pleno to represent light fields, point clouds, and holograms. Among them, JPEG Pleno Holography is the first international standard for hologram compression. We review recent advances in JPEG Pleno Holography standardization and discuss future directions of development.

• The Journal of Asian Finance, Economics and Business
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• 제7권12호
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• pp.1005-1015
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• 2020

This paper aims to propose a Comprehensive Decision Support Model to evaluate retail companies' financial performance traded on the Vietnam Stock Exchange Market. The financial performance has been examined in terms of the valuations ratios, profitability ratios, growth rates, liquidity ratios, efficiency ratios, and leverage ratios. The data of twelve companies from the first quarter to the fourth quarter of 2019 and the first quarter of 2020 were employed. The weights of 18 chosen financial ratios are calculated by using the Standard Deviation method (SD). Grey Relational Analysis technique was applied to obtain the final ranking of each company in each quarter. The results showed that leverage ratios have the most significant impact on the retail companies' financial performance and gives some long-term investment recommendations for stakeholders and indicated that the Taseco Air Services Joint Stock Company (AST), Mobile World Investment Corporation (MWG), and Cam Ranh International Airport Services Joint Stock Company (CIA) are three of the top efficient companies. The three of the worst companies are Viglacera Corporation (VGC), Saigon General Service Corporation (SVC), and HocMon Trade Joint Stock Company (HTC). Furthermore, this study suggests that the GRA model could be implemented effectively to ranking companies of other industries in the future research.

• 조명전기설비학회논문지
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• 제29권12호
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• pp.47-54
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• 2015

Normally, multiple socket-outlet is manufactured with soldered, welded permanent connection (termination). Because this procedure is very non-environmental and requires many labor forces, many companies skip this process. To solve this these problems, this research had to design permanent joint type multiple socket-outlet, develop safer multiple socket-outlet than is sold in markets. Progressing this research, we took 3 steps. First, we had to design device for fixing a frame suitable for multiple socket-outlet. Second, this multiple socket-outlet must pass fundamental standards through international standard (IEC 60884-1) and Korean standard (K 60884-1) tests. Third, it had to pass both several mechanical and electrical tests which is more strict than fundamental standards and vibration and impact tests following KS standards for enhancing its safety. After finishing 3 steps, we could obtain objective and fair data, develop environmental permanent joint type multiple socket-outlet without soldering crimped connection.

• 한국인쇄학회:학술대회논문집
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• 한국인쇄학회 2000년도 춘계 학술발표회 논문집
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• pp.17-24
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• 2000

The Joint Photographic Experts Group (JPEG) is a standara still-image compression technique, established by the International for Standardization (ISO) and International Telecommunication Standardization Sector (ITUT). The standard is intended to be utilized in the various kinds of color still imaging systems as a standard color image coding format. Because JPEG is a lossy compression, the decompressed image pixel values are nto the same as values before compression. Image of JPEG compression is often made to JPEG recompression at saving to apply JPEG compression of color image. In general, JPEG is a lossy compression and compression image is predicted to be varied image quality according to recompressed Q-factor. Various distortions of JPEG compression and JPEG recompression has been reported in previous paper. In this paper, we compress four difference color samples (photo image, gradient image, vector drawing image, text image) according to various Q-factor, and then compressed images are recompressed according to various Q-factor once again. As the results, we inspect variation of quality and file size of recompressed color image, and ensure the optimum recompression factor.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2001년도 추계 기술심포지움
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• pp.67-73
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• 2001

To investigate the relationships of solder joint characteristics with solder composition and A:V ratio (solder volume per pad area), Sn-37Pb and Sn-4.0Ag-0.5Cu solder balls with 330, 400, 450 and $457{\mu}{\textrm}{m}$ size were reflowed on same substrate. Sn-37Pb and Sn-4.0Ag-0.5Cu was reflowed at $220^{\circ}C$ and $240^{\circ}C$ respectively by IR-type soldering machine. As a result of reflowed solder- ball diameter(D) and height(H) measurement, D/H was decreased with solder ball size increment in range of 330~450 ${\mu}{\textrm}{m}$. But, D/H was increased in the solder joint for 457 ${\mu}{\textrm}{m}$ size, it was caused possibly by decrement of solder ball height increment compared with solder volume increment. As a result of shear and pull test, joint strength with A:V ratio was high. Joint strength of Sn-4.0Ag-0.5Cu was higher than Sn-37Pb. However, Sn-37Pb had more stable solder joint of small standard deviation. A thick and clean scallop type Ni-Cu-Sn intermetallic compound layer was formed in high A:V ratio and Sn-4.0Ag-0.5Cu solder joint interface.

• 한국식품위생안전성학회지
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• 제1권1호
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• pp.77-95
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• 1986

In 1962 the governing bodies of FAO and WHO approved the establishment of a joint FAO/WHO Food Standards Programme, the creation of a jointly sponsored body to be known as the Codex Alimentarius commission to implement the Programme. It can reasonably be claimed that the Commission has assumad the leading role in establishing internation food standards throughout the world. The Codex Committee of Food Hygiene has received much advice and assistance from other international organization which have been working in this field for a number of years. In particular, it has received valuable background documentation from the International Commission on Microbiological Specifications for Foods(ICMSF) which was set up by the International Association of Microbiological Societies(IAMS), and also from the International Organization for Standardization (ISO). Nevertheless, in spite of the information supplied by governments and research bodies in this field, microbiological standards have proved to be a highly controversial subject from the point of view of Codex standards. When it is decided to establish a microbiological standard for a food or class of foods, the following technical and administrative aspects must be considered: 1) The standard should be based on factual studies and serve one or more of the following objectives: (1) to determine the conditions of hygiene under which the food should be manufactured; (2) to minimize the hazards to public health; (3) to measure the keeping quality and storage potential of the food 2) The standard should be attainable under practicable operating and commercial conditions and should not entail the use of excessive heat treatment or the additions of extra preservatives. 3) The standard should be determined after investigation of the processing operation. 4) The standard should be as simple and inexpensive to administer as possible, the number of tests being kept to a minimum. 5) Details of methods to be used for sampling, examining and reporting should accompany all published microbiological standards. 6) In establishing tolerance levels for the permissible number of defective samples, allowance should be made for sampling and other variations due to differences in the laboratory methods. The following additional points should be kept in mind: 1) It is not satisfactory to establish one set of microbiological standards for a miscellaneous group of foods, such as“frozen foods”or“precooked foods”. 2) Microbiological standards should be applied first to the more hazardous types of food on the basis of experience of expected microbiological levels, taking into account variations in composition, processing procedures, and storage. 3) When a standard is established, there should be a definite relationship between the standard and the hazard against which it is meant to protect the public. 4) The sensitivity, reliability, and reproducibility of the sampling and analytical methods should be compared in different laboratories and the methods to be used should be specified in detail as part of the standard. 5) Tolerances should be included in the standard to account for inaccuracies of sampling and analysis. 6) Standards should be applied on a voluntary basis before compliance is made mandatory.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 A
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• pp.504-506
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• 1993

JPEG(Joint Photographic Experts Group) 표준안은 디지털 정지 압축을 위하여 국제표준화기구(ISO/SC29/WG10)와 국제전신전화 자문회의(CCITT SG VIII)에 의해서 제안되었다. JPEG 표준안은 전자영상, 컴퓨터 그래픽, 멀티미디어 등과 관련하여 널리 응용되고 있으나, 의료 영상분야에서는 JPEG 압축의 손실 특성 때문에 사용이 매우 제한적이었다. 본 논문에서는 JPEG 표준안을 핵자기 공명 단층 영상 (256 gray levels, $256{\times}256$ size) 압축에 적용하여 그 성능을 조사하였다. 이를 위하여 JPEG 표준안 중 DCT에 기반을 둔 순차식 부호화 압축을 C-Cube Microsystems의 CL550 chip을 사용하여 구현하였고, 점진식 및 무손실 부호화 방식은 특별한 Hardware 없이 Software로 구현하여 실험하였다. 본 실험을 통하여 핵자기 공명 단층 시험 영상에 대해 거의 왜곡없이 약 10-20 정도의 압축률이 얻어짐을 확인할 수 있었다. 특히 JPEG으로 압축하였을 경우 재구성한 영상과 원영상과의 에러 신호가 random noise에 가깝게 나타남으로써 특별한 artifact가 없는 것도 JPEG의 큰 장점으로 부각된다. 한편 JPEG의 점진식 및 게층식 부호화 방식은 압축률과 신호대 잡음비에 있어서는 순차식과 동일하나, 거대한 영상 데이터 베이스 내에서의 빠른 탐색과 비교적 속도가 느린 공중망을 통한 원격 진단에 유용한 특성을 갖는다.